Any tips on homemade scent-free transdermal?

I've tried several of the transdermal carriers on the market, including Penetrate, and all got the thumbs-down from a SO who is somewhat sensitive to certain smells. I didn't care for the scents, either.

I've used straight isopropyl alcohol, like the old Biotest Androsol, and that is certainly scent-free when dry, but it leaves a fair amount of the active on the skin, so penetration is not very good.

What is a decent transdermal formula that would have good penetration, but not much, if any, scent?